Reaction products of di-chloro-dioxane and the halo-organic acids



Patented Feb. 20, 1940 ar s areas"; 1

Harold Slagh, Midland, Mich, assignor to The Dow Chemical Company,Midland, Mich, a corporation of Michigan No Drawing. Application august28, was, i Serial No. 161,469

9 Claims.

This invention concerns ester products of the reaction between1,4-dioxanediol-2B and the halogen-substituted carboxylic acids.

I have discovered that the halogen-substituted carboxylic acids reactwith 2,S-dich1oro--dioxane- 1,4 to form. valuable ester products.Di-esters of l,l-dioxanediol-2,3 and mono-esters of 2-chlorodioxaneol-3can be prepared by heating 2,3-di- .chloro-dioxane-1,l withhalogen-substituted carboxylic acids and thereafter separating thedesired ester products from the reacted mixture. In carrying out thereaction, the acid and dichloro-dioxane are mixed together and warmed toa temperature at which hydrogen chloride is evolved from the mixture.Following completion of the reaction, the crude reaction mixture istreated to recover the desired ester products.

While the halogen-substituted carboxylic acid and dichloro-dioxane canbe reacted together in varying proportions, I generally employ fromabout 0.5 to about 2.25 molecular equivalents of acid for each mole ofdichloro-dioxane present in the reaction mixture. A mixture of thediesters of l/l-dioxanediol-ZB and the mono-esters ofZ-chloro-dioxaneol-B is generally formed, the di-ester being formed inincreasing proportion as the ratio of acid to dichloro-dioxane in thereaction mixture increases.

, The preferred reaction temperature varies with the particular acidemployed but is generally between about 100 C. and the decompositiontemperature of the reaction mixture, although somewhat lowertemperatures may sometimes be employed. If desired, the reactants may bedissolved inan inert solvent such. as benzene, chloro-benacne, toluene,xylene, etc, and the reaction carried out by heating the mixture at itsrefluxing temperature. time required for carrying out the reaction isdependent upon the reaction ternperature employed and whether a monoordiester compound is desired as the major product of reaction.

The methods by which the ester products are isolated from the crudereaction mixture vary with the particular compounds concerned. Forexample, in isolating the ester derivatives or" low boiling and stableacids, the crude reaction prod uct may be fractionally distilled underreduced pressure. When high boiling or unstable acids are employed thereaction, the crude mixture resulting therefrom may be partiallydistilled under reduced pressure to recover low boiling products ofreaction and unreacted acid and dichloro-dioxane, and subsequentlyfractionally crystallized, clarified with activated carbon, or

selectively extracted with solvents adapted to effect separation betweenthe desired ester de rivatives and residual reactants present therein.When the ester products formed are insoluble, a preliminary separationcan be accomplished by filtering the reaction mixture. i

The products obtained by reacting different halogen-substitutedcarboxylic acids with 2,3-di chloro-dioxane-Li vary in characteristicfrom a stable crystalline compounds of definite melting 10 point tounstable, viscous liquids whichdecompose distillation and have thecharacteristic of rapid polymerization upon exposure to air and light.These compounds have been found useful for a number of purposes, e. g.as plasticizers, insecticidal agents, intermediates, etc.

The following examples set forth the characteristics and method ofpreparation for certain rep resentative members of my new class ofcompounds but are not to be construed as limiting 20 the invention.

Example 1 This product was somewhat light-sensitive, and

The chlorine 35 had a sharp, penetrating odor. content thereof, asdetermined by analysis, was 24.45 per cent by weight.

Example 2 In a similar manner 79 grams (0.5 mole) of2,3-dichloro-dioxane-1A and milliliters of toluene were refluxed with129 grams (1 mole) of dichloro-acetic acid at temperatures increasingfrom 98 C. to 124 C. over a period of 4 hours. The reacted product wasthereafter cooled and distilled under vacuum whereby there was obtained72 grams of the di-(dichloro-acetate) of l.,4.-dioxanediol-2,3 as ayellow tinged, viscous liquid boiling at 1635 174 C. at 0.15 inchpressure, and having a specific gravity of 1.556 at 25/25 C.

Example 3 A mixture of 104: grams (0.56 mole) of 4-chlorobenzoic acid,52 grams (0.33 mole) of 2,3-dichlorodioxane-l/l, and 125 milliliters ofxylene was refluxed at -l50 C. for 5 hours. The reaction residue washedwith xylene and dried.

138, grams (0.5 mole) of symmetrical dibromo- ,sucoinic acid, 39.5 grams(0.25 mole) of 2,3-dichloro-dioxane-l,4 and 100. milliliters of xylenewere mixed together and refluxed at 134 C. for 2.5 hours. Filtration ofthe reaction mixture resulted in the recovery of 64 grams of startingacid as a residue. Fractional distillation of the filtrate yielded anadditional 43 grams of unreacted acid and 52 grams of adi-(symmetrical-dibromo-suocinate) of 1,4-dioxanediol-2,3 product as adark, syrupy liquid which decomposed on attempted distillation.

Other acids which may be reacted with 2,3-diohloro-dioxane-1,4 in amanner analogous with that described in the foregoing examples includethe following: alpha-bromo-butyric acid, monobromo-acetic acid,-chloro-pyromucic acid, polychloro-stearic acid, 2,4,6 tri chlorophenoxyacetic acid, alpha-bromo-cinnamic acid, 2-chlorobenzoic' acid, 4chloro alpha naphthoic acid, alpha-chloro-crotonic acid,beta-bromo-crotonic acid, 2,4-dichloro-phenyl-acrylic acid, etc. Ifdesired, mixtures of the above and similar halogensubstituted carboxylicacids may be reacted with 2,3-dichloro-dioxane-L4 to obtain di-esterproducts in which the esterifying groups are not identical. Similarly,mono-esters of 2-chloro-dioxaneol-3 can be reacted with thehalogen-substituted carboxylic acids to give mixed di-esters of Othermodes of applying the principles of my invention may be employed insteadof those explained, change being made as regards the materials employed,provided the products described in the following claims be therebyobtained.

I therefore particularly point out and distinctly claim as my invention:

1. The di-ester of 1,4-dioxanedi0l-2,3 and a halogen-substitutedcarboxylic acid.

2. The (ii-ester of 1,4-dioxanediol-2,3 and a halogen-substitutedmono-carboxylic acid.

3. The di-ester of l,4-dioxanediol-2,3 and a halogen-substitutedaromatic carboxylic acid.

4. The di-ester of 1,4-dioxanediol-2,3 and a halogen-substitutedaliphatic carboxylic acid.

5. The di-ester of 1,4-dioxanediol-2,3 and a chlorine-substitutedaliphatic carboxylic acid.

6. The di-ester of l,4-dioxanediol-2,3 and a chlorine-substituted fattyacid.

7. Di-(monochloro-acetate) of 1,4-dioxanediol- 8. Di-(dichloro-aoetate)of 1,4-dioxanediol- 2,3. i

9. Di-(4-chloro-benzoate) of 1,4-dioxanediol- 2,3.

HAROLD R. SLAGH.

